1. Field of the Art
This invention relates to a method and an apparatus for recording (writing) or reproducing (reading) information by using optical information-recording media, such as optical cards, optical disks or the like, and more particularly relates to a method and an apparatus for recording in and reproducing from card-like optical information recording media, i.e., optical cards, in which tracks for the purpose of tracking are provided.
2. Prior Art
Heretofore, as optical information-recording media of this kind, so-called write-once type optical cards in which it is possible to record only once, and to reproduce a plurality of times are well known. In the write-once optical card, information is recorded as a row of pits (information tracks) which are optically detectable, by focusing a light beam which is modulated according to the information to be recorded into a minute light spot by a lens, and by irradiating and scanning the minute light spot on an information-recording region of the optical card. Since it is necessary to arrange the row of pits systematically, for example rectilinearly, and with a predetermined interval in the information-recording region for the convenience of reproducing information, there have hitherto been provided tracks for the purpose of guiding in write-once type optical cards.
The provision of the tracks for guiding is, however, a cause which hinders increase of the information-recording capacity.